Senegalese President Abdoulaye Wade said on Monday he would pull his country's troops out of Darfur if it was determined that African peacekeepers who were killed at the weekend were not equipped to defend themselves.

Twenty AU soldiers were killed or injured and 40 missing after a "deliberate and sustained" assault on the Haskanita base in Darfur on Saturday night by armed men in 30 vehicles, who looted and destroyed the base, the African Union said.

The attack, which is being blamed on rebel factions, was the worst single attack on AU forces since the 7,000-strong mission was deployed to western Sudan in 2004.

"If they died because they didn't have the arms to defend themselves, I will withdraw all the Senegalese ... I am not going to send people to be slaughtered," he said, adding he had ordered an investigation into the attack.

The AU has long complained of a lack of equipment in Darfur, including attack helicopters and rapid response vehicles. They have also said their force was too small to contain the conflict in the vast and arid region the size of France.

Senegal has one of the largest contingents in Darfur and has taken casualties in the past. Most of the infantry in Haskanita was Nigerian but military observers were from various countries.

AU spokesman Assane Ba said seven of those killed were Nigerian, one Senegalese, a Malian and one from Botswana.

"AU peacekeepers will remain in Darfur until the United Nations-African Union Hybrid Operation will be deployed," he said from AU headquarters in Ethiopia.

While AU convoys and individuals have been ambushed -- around 40 killed in the three years prior to the Haskanita attack -- this was the first time an entire base was targeted.

AU force commander Martin Luther Agwai said the mission was making contingency plans and reassessing security. But he said little more could be done without getting desperately needed additional equipment and troops into Darfur.

"People did deployment on the premise that there was an (peace) agreement and they were coming to inspect and act as observers -- there was no planning for people to be able defend themselves," Agwai said.

URGENCY

Experts estimate 200,000 people have died and 2.5 million driven from their homes as mostly non-Arab rebels in Darfur took up arms in early 2003 accusing the government of neglect. Khartoum mobilized mainly Arab militias to quell the revolt.

The AU mediated a peace agreement between the Sudanese government and Darfur rebels in May 2006 but only one of three rebel negotiating factions signed the deal. Since then, rebels have split into a dozen factions.

The violence, which includes militias and tribal conflicts, has severely curtailed the world's largest aid operation.

Saturday's attack casts a shadow on AU-U.N.-mediated talks due to begin in Libya on October 27. Mediators Salim Ahmed Salim and Jan Eliasson expressed "shock and dismay" at the attack.

Condemnation over the attacks came in from around the world -- from the Arab League to Washington.

White House spokeswoman Dana Perino said the violence underscored the urgency of the AU-UN mission.

"Obviously what the president (George W. Bush) wants is that U.N. peacekeeping force to get there as soon as possible because we are committed to ending the violence and providing assistance to the people who are suffering there in Darfur," she said.

Suleiman Jamous, a member of the Sudan Liberation Army (SLA) Unity faction which is one of two groups accused of the attack, said if his faction was involved in the attack it was a local decision, not ordered by the leadership.

"I have asked the leadership of SLA Unity to withdraw all the troops from the area, to where they can be under the direct control of the military command," Jamous said.

SLA Unity and a breakaway faction of the Justice and Equality Movement (JEM) led by Bahr Idriss Abu Garda have forces in the Haskanita area. Other JEM commanders said Abu Garda and a SLA Unity commander had the stolen AU vehicles.

SLA Unity military chief Abu Bakr Kadu has denied his forces had attacked the AU base, saying the African troops may have been caught in the crossfire between fighting with the army.

The attack preceded a visit of "elders" to Sudan, including South African Archbishop Desmond Tutu, ex-U.S. President Jimmy Carter, veteran peace mediator Lakhdar Brahimi and women's and children's rights advocate Graca Machel.

On Monday they met Sudanese President Omar Hassan al-Bashir, but declined to discuss the 90-minute talks until the end of their trip when they meet Bashir again.